Process and agent for carroting furs



Patented Dec. 3,.192 9.

PATENT OFFICE mom r. mvmrwonrn, or nnmonroar; commences rnocnss Aim AGENT roacaanorm'e runs at Drawing. pplication men April 4,

This inventionfelates to processes of and compositions for treating fur or like material preparatory to felting and it comprises a process in which fur is subjected to the action of an aqueous solution containing chloric or perchloric acid advantageously, altho not necessarily together with nitric acid; it further comprises a for treating solution composed at least in part of chloric or perchloric m acid and nitric acid in aqueous solution; and

it further comprises the fur so treated. In preparing fur for felting purposes, it is j customer practice to treat the for with various c emicals coming under the general n head of carroting agents. Such substances act to remove the waxy or gummy material with which the'individual fibres of fur are normally coated or sheathed at least in part. he is well recognized, the individual fur fibres no have a number overlying scales-or barbs forming apart 0 the fibre structure. These barbs makeit possible to felt the individual fibres into a felted mass because the barbs of one fibre interlock with the herbs of another my material referred to obscures the herbs and renders them ineffective during the letting operation unless the wax is removed rfir to felting in order to fully expose the a a. Y

@arroting agents have-the property of removing thls wa material or rendering it soluble. Hereto ore, mercuric nitrate has been widely employed as a carroting agent, the fur bein treated with aqueous solutions thereof. Aside from the essentially poisonone character of mercuric nitrate, it is a disadvantageous material to use for many other there is about a half reasons. -While other carroting agents have been sug ested to supplant mercuric nitrate, none of t em can be said to as effective as this material." There is thus real necessity for a carroting composition which is at least, if not more, effective than mercuric nitrate, or other mercu compounds, being, however, free from the iDJUl'iOll-S toxic eifects associated with salts of mercury. r

I have found that perchloric-acid, or chloric acid, which can also be used in con unction on with an aqueous solutionof nitric acid, is an dill during the felting operation. The waxy or' 1928. Serial in. 267,477.

excellent carroting agent and possesses all'the tion of chloric or perchloric acid rapidly re 5 movesithe waxy or gummy material normally obscuring the barbs of the fibres and expeditiously prepares the fur for the felting operation. The resulting carroted fur is free from mercury compounds and can thus be cc subjected to the subsequent operations without having any toxic'eifect upon the workman. Fui'thermorathe fibre co're is not weakened, altho when salts of mercury are used, it is well-recognized that the fibre core suffers a 05 loss in strength.

My-carroting solution can be prepared in various ways, depending somewhat on its composition. Whenusing an aqueous solution of chloric acid, having the formula in HClO I ordinarily 'add nitric acid to a solution of barium chlorate in quantity suflicient to react with the barium chlorate. Barium chlorate is an advantageous chloratev to use 'altho' I can use other chlorates such as the alkali metal chlorates. The nitric acid acts to displace the chloric acid from its salt, thus formingfree chloric acid in situ. An excess of nitric acid is not detrimental and infect the presence oi? some free nitric acid is ad eu vantageous. I

As a specific example, I make up an aqueous solution of one pound of barium chlorate in three pounds of Water and add thereto one pound of nitric acid. Sufiicient nitric acid is an added to react with all the barium chlorate andthen a further quantity is added so that und of free nitric acid m the solution whic now contains free chloric acid. In this ex 'mple, the total quan- 9o tity of solution amounts tofive and a half pounds, and this is enough to treat about five pounds of fur. In neral, it can be said that the final olution si ould have a strength of from eight to twenty degrees Banana.

When using perchloric acid, I make up a solution containing about one pound of atilfiffiFbrchlomta and add to it about one and a pounds ofnitric acid so that the final solution has a. concentration in free nitric 20 tained.

tains dissolved barium nitrate, but this is not to be regarded as a detriment.

If I wish to use a'chloric acid solution "wholly free of dissolved salts, I can first prepare an aqueous solution of chloric acidby adding sulphuric acid to an aqueous solution of barium chlorate. The barium sulphate formed is filtered ofi, and to the resulting aqueous solution of chloric acid I add nitric aciduntil the desired concentration isob- In each of the above examples, it will be observed that inevery instance, the carroting solution is essentially composed of the two active ingredients, nitric acid and a chloric acid,

' the term a chloric acid being used to collectively denote chloric or perchloric acid, the latter having the formula HClO When I wish to employ a solution containing chloric or erchloric acid andbeing free so of nitric acid, decrease the amount of nitric acid added to the chlorate or perchlorate so v that just enough .acid is added to react. The

exact uantity ofnitric acid to be added can be me; 'ly determined by stoichometrical calculations, one molecular weight of barium chlorate or perchlorate requiring two molecular weights of nitric acid to fully displace all of the chloric or rchloric acid.

The solution 0 chloric or perchloric acid 40 containing nitric acid if desired, advantageously prepared in one of the above ways, is r then applied to the fur.- Inasmuch as the solution is very free flowing, it soon reaches all parts of the fur and aregular and uniform treatment is easily secured. It is equally adaptable to manualor machine application. If desired, the fur can be removed from the skin before being treated with the solution, thereafter treated and subsequently dried. While I haveset forth speclfic examples of ways to prepare my solution, itis, of course, understood that the details and proportions may be varied within wide limits. The most advantageous concentration of chloric or rit chloric acid and nitric acid is best determined for each particular batch of fur treated. especially when variation in the quality or other characteristics is sus v The carroted fur, prepared in accordance I with the present invention is far superior in appearance,strength and texture to carroted fur prepared "with carroting agents hitherto proposed. I attributethis to the fact that my carroting solution, while it acts rapidly on the waxy or gummy substances coating the fur fibres, has little or no effect upon the fur fibre itself, and, if anything, it increases the natural sheen and brilliancy, possibly because the treated fur fibres may have upon thema small quantit of material representing the' reaction f) not of the natural wax with the acids 0 my Theearroted fur prepared in accordance with my present invention is more readily blown and felted and when so felted is more readily dyed, this too being attributed to thefact that the fur fibre is uninjured. Because of the superior felting qualities, it is possible to mix in a larger percentage of rougher or cheaper fur stock without serious disadvantage when it His desired to use mixed stocks of var ua lii ti e appe ded claims, it is to be understood that by the expression a chloric acid, I mean to include both chloric and perehloric acid, the latter being generically denoted as a chloric acid.

Having thus .described my invention, what I claim is:

1. The process of treating fur which comprises treating the fur with a carroting solu tion comprising an aqueous solution of a chloric acid.

2. The process of treating fur which comprises treating the, fur with a carro solution comprising. 'an aqueous solution of chloric acid.

prises treatingthe fur with a carroting solution comprising an aqueous solution of a chloricacid, the solution having a of from about eight to twenty degrees Baum.

4. The process of treating fur which comprises treating the fur with a carroting solution comprising an aqueous solution of chloric acid} the solution havin a strengthof from eightto twenty degrees dhum.

5. A solution for treating furs comprising an aqueous' solution of nitric acid and '-a chlork acid. f

6. soution ortr'ea furscom an aqueous solution d f nitric aci d and chloric acid.

7. A solution for trea furs comprising an aqueous solution of mtric acid and a chloric acid, the. solution having a of from eight to twenty degrees Baum.

8. A solution for treat" furs comprising an aqueous solution of nitric acid and chloric acid, the solution ha a strength eight to twenty degrees aum.

t). The process of treating fur which comprises treating the fur with a carrot' solution comprising an a ueous solution' d fnitric acid and achloric aci The process of treating fur which comprises treating the fur with a-carro solut on comprising an aqueous solution 0 nitric acid and chloric acid.

3. The process of fur which comcarroting composition.

of from 11. The process of treating fur which comprises treating the fur with a carroting solu-' tion comprising an aqueous solution of nitric acid and a chloric acid, the solution having a strength of from about eight to twenty degrees Baum;

12. The process of treating fur which comprises treating the fur with a carroting solution comprising an aqueous solution of nitric acid and chloric acid, the solution having a strength of from about eight to twenty degrees Baum. v

Signed at Bridgeport, this 31st day of March, 1928. I

HAROLD T. LEAVENWORTH. 

